Using mutant human α-syn-overexpressing mice injected with DSP-4, we studied 1) temporal relationship among inflammation, α-synucleinopathy and neuronal loss in colon and 2) effects of elimination of colon inflammation by anti-inflammatory agents, such as long-lasting β2-adrenoreceptor (β2-AR) agonist salmeterol or NADPH oxidase (NOX2) inhibitor dipheyleneiodonim (DPI), on α-synucleinopathy and neuronal loss in colon as well as the defecatory dysfunction. The gene discussed is ADRB2; the disease is synucleinopathy.